Update instructions webview

As of v4.31.0, @appland/components has a new install guide flow.

The major changes are as follows:

The guide is now a single page instead of multiple steps
The guide no longer makes use of detected language, web framework or test framework
The guide no longer makes use of any dynamic installation status

Any existing links or buttons to open the install guide (install the agent, record data) should simply open this view. There's no longer a need to select or set a specific page as there was before.

Any existing code related to language, web or test framework detection can be removed. The same goes for milestone progress in the installer (i.e., the check boxes in the sidebar).

A new, unobtrusive button should be added to open the install guide. This is separate from the existing link to create AppMap data when none is present (that can stay). In Visual Studio Code it's currently a small button on the "AppMap Data" section within the sidebar, but it could also suffice to add a menu bar button, etc. Anything will do as long as it does not present itself in a way that may pull users away from the big Navie button in the sidebar.

getappmap / appmap-intellij-plugin

Update instructions webview #776